I've finally realized that my camellia's ongoing flowering
problems might be due to having it in the wrong kind of
container. This year, the flowers didn't seem to have blight,
but only a few opened; the other buds dried up. I took some
leaves to a local highly regarded nursery, and their diagnosis
was edema. So I think the poor thing has wet feet.

The pot is glazed ceramic, with only one small drain hole.
I just found a reference to someone who carefully drilled
additional holes in a glazed pot to keep his camellia happy.
I have a friend who owns a good collection of masonry bits,
so that's one possibility.

Or should I switch to another type of pot entirely? E.g.
non-glazed ceramic (would that make the soil dry out *too*
fast??), or plastic with a lot of drainage holes?


Patty

On 8/30/2008 1:26 PM, Patty Winter wrote:
I've finally realized that my camellia's ongoing flowering
problems might be due to having it in the wrong kind of
container. This year, the flowers didn't seem to have blight,
but only a few opened; the other buds dried up. I took some
leaves to a local highly regarded nursery, and their diagnosis
was edema. So I think the poor thing has wet feet.

The pot is glazed ceramic, with only one small drain hole.
I just found a reference to someone who carefully drilled
additional holes in a glazed pot to keep his camellia happy.
I have a friend who owns a good collection of masonry bits,
so that's one possibility.

Or should I switch to another type of pot entirely? E.g.
non-glazed ceramic (would that make the soil dry out *too*
fast??), or plastic with a lot of drainage holes?


Patty


A clay pot or unglazed ceramic pot will indeed dry quickly. However, in
drying, it will keep the roots cool. I highly recommend a clay pot at
least 18 inches in diameter. Merely water the plant more often.

If you want, you can put a clay or unglazed ceramic pot inside a larger
glazed pot; just put an inch or two of pea gravel at the bottom of the
glazed pot. Nevertheless, the glazed pot still needs a drainage hole.
Put a piece of window screen over the hole so that the pea gravel does
not leak out.

Plant the camellia in my do-it-yourself potting mix, which will stay
moist without getting soggy (providing the pot is allowed to drain).
See http://www.rossde.com/garden/garden_potting_mix.html.

An 18-inch pot requires much more mix than the basic recipe produces.
Camellias are indeed acid loving; for a large batch of mix, use three
parts of peat moss to two parts sand. However, camellias prefer a
"lean" soil. Thus, use the amount of nutrients indicated in the recipe
even though you are preparing much more mix; DO NOT increase the
nutrients in proportion of the amount of mix. Include the zinc sulfate
(if you can find any) and the pinch of soil sulfur.

--
David E. Ross
Climate: California Mediterranean
Sunset Zone: 21 -- interior Santa Monica Mountains with some ocean
influence (USDA 10a, very close to Sunset Zone 19)
Gardening pages at http://www.rossde.com/garden/

In article ,
David E. Ross wrote:

A clay pot or unglazed ceramic pot will indeed dry quickly. However, in
drying, it will keep the roots cool. I highly recommend a clay pot at
least 18 inches in diameter. Merely water the plant more often.

David, are you saying that you would recommend those options
instead of a glazed pot? I.e., am I asking for trouble by
having it in a glazed pot? Or would that be okay if I drilled
more holes in it?

If you want, you can put a clay or unglazed ceramic pot inside a larger
glazed pot; just put an inch or two of pea gravel at the bottom of the
glazed pot. Nevertheless, the glazed pot still needs a drainage hole.
Put a piece of window screen over the hole so that the pea gravel does
not leak out.

Oh, that's a nifty idea!

Plant the camellia in my do-it-yourself potting mix, which will stay
moist without getting soggy (providing the pot is allowed to drain).
See http://www.rossde.com/garden/garden_potting_mix.html.

That looks like a very good solution. (And I did see your followup
comments about the right mixture for a large planter.) Moist but
with good drainage is exactly what I need for a lot of my plants,
and they sure don't get it with adobe...


Thanks!
Patty

On 8/30/2008 9:07 PM, Patty Winter wrote [in part]:

David, are you saying that you would recommend those options
instead of a glazed pot? I.e., am I asking for trouble by
having it in a glazed pot? Or would that be okay if I drilled
more holes in it?


Because a glazed pot does not allow moisture through it (which cools the
pot), it can cause roots to cook if the sun shines on the pot. In your
case -- with a camellia -- this should not be a problem because
camellias require shade (bright indirect light but no sun at all).

You might mix some pea gravel with the potting mix or use decomposed
gradate (DG) in place of sand. (The DG should be the consistency of
coarse sand.)

The native environment of camellias is in the foothills of the
Himalayas, in the finer DG that has washed out of the mountains. This
soil has perfect drainage. The area has almost constant cloud cover (no
full sun) with continuous drizzle as the prevailing winds push moist air
from the Indian Ocean up the mountain slopes. The drizzle not only
keeps the gritty soils moist but also leaches away most nutrients.
Further, areas with frequent rain tend to have acidic soils.

To recreate that environment, you need a lean, acidic potting mix that
drains very well. You need to keep the plant in the shade. (This
applies primarily to C. japonica; C. sasanqua can tolerate part-sun.)
And you need to water frequently but lightly. In general, feed the
plant only once a year, right after blooming; use a commercial camellia
food (usually also for azaleas and rhododendrons), which is relatively
low in nitrogen and releases the nutrients very slowly.

Camellias do not need pruning to improve flowering. They only need
pruning for aesthetic reasons (e.g., shape, size). In your case (the
plant in a container), you might also have to prune to keep the foliage
from exceeding the ability of constrained roots to supply moisture; in a
large pot (18 inches or more), however, this might not be needed. If
you do prune, do it right after blooming and before feeding.

If you move a camellia (i.e., repot it), the best time is while it is
blooming. Although it doesn't lose its leaves then, it is actually
dormant when in bloom.

--
David E. Ross
Climate: California Mediterranean
Sunset Zone: 21 -- interior Santa Monica Mountains with some ocean
influence (USDA 10a, very close to Sunset Zone 19)
Gardening pages at http://www.rossde.com/garden/

In article ,
David E. Ross wrote:

Because a glazed pot does not allow moisture through it (which cools the
pot), it can cause roots to cook if the sun shines on the pot. In your
case -- with a camellia -- this should not be a problem because
camellias require shade (bright indirect light but no sun at all).

Yep, it's in the shade!

To recreate that environment, you need a lean, acidic potting mix that
drains very well. You need to keep the plant in the shade. (This
applies primarily to C. japonica; C. sasanqua can tolerate part-sun.)
And you need to water frequently but lightly. In general, feed the
plant only once a year, right after blooming; use a commercial camellia
food (usually also for azaleas and rhododendrons), which is relatively
low in nitrogen and releases the nutrients very slowly.

Ah, good thing I'm bad about remembering to feed my plants. :-)

In your case (the
plant in a container), you might also have to prune to keep the foliage
from exceeding the ability of constrained roots to supply moisture; in a
large pot (18 inches or more), however, this might not be needed.

I just checked yesterday, and although the plant has been in that
pot for 2-3 years, it is nowhere near being rootbound. And the
foliage hasn't gotten much larger. So I think we're okay on size.

If you move a camellia (i.e., repot it), the best time is while it is
blooming. Although it doesn't lose its leaves then, it is actually
dormant when in bloom.

Oh, that's interesting. Well, I may repot it now anyway, to improve
its chances for proper drainage between now and the next blooming
season. Thanks for the ideas!


Patty